The Diving Gear Mod for 1.4.7 adds three different helmets that increase how long you can stay underwater by giving you more air when you run out.
Diving Gear Mod Features:
Snorkel:
Increases air by 1.5
Atmospheric Diving Suit:
Doubles air capacity
Scuba Helmet:
Single Tank is 3x air capacity and Double Tank is 6x air capacity
Recipes:
Snorkel:
Atmospheric Diving Suit:
Scuba Helmet (Single Tank):
Scuba Helmet (Double Tank):
Single Air Tank:
Double Air Tank:
Download Diving Gear Mod for 1.4.7:
Diving Gear Mod for 1.4.7
Forge for 1.4.7
Installation:
Locate your Minecraft.jar file.
Delete the META-INF folder
Drag the files...

Minecraft has been updated to 1.4.7. This updated fixes many of the bugs found in 1.4.6 including:
Fixed joining a server, and leaving it, then trying to connect to another server crashing the game
Fixed bold text taking up lots of space in chat
Fixed the server crashing when an arrow shot...